Wireless power transfer systems can be used to charge various loads in electronic devices. A wireless power transfer system has an advantage that a physical connection to a charging unit is not required. Thus, there is no requirement for the electronic device to have an external connection port to be coupled to a charging unit or charging station.
A wireless power transfer system includes a transmitting circuit and a receiving circuit. The receiving circuit typically includes a reception coil and energy is transferred from the transmitting circuit, which also has a coil via induction. Accordingly, the receiving circuit will resonant based on a tuned resonant frequency.